The analysis is published online as a Web First article byHealth Affairsand will also appear in the journal’s June issue.

The study found that among people who enrolled in individual marketplaces, those who enrolled earlier were older and used more medication than later enrollees. Marketplace enrollees, as a whole, had lower average drug spending per person and were less likely to use most medication classes than patients enrolled in employer-sponsored health insurance. However, marketplace enrollees were much more likely to use medicines for hepatitis C and for HIV.

“Not since the 1960s has the United States seen an expansion of insurance coverage like that produced by the ACA, with millions of Americans enrolling in the first year,” said lead author Julie M. Donohue, Ph.D., associate professor and vice chair for research in Pitt Public Health’s Department of Health Policy and Management. “The insights gained by our analysis have implications for the marketing of ACA insurance plans, benefit design and out-of-pocket costs, as well as public health ramifications, such as expanding treatment for infectious diseases like HIV and hepatitis C.”

Dr. Donohue and her team looked at data on medication use from January through September 2014 on 1 million ACA-established marketplace insurance plan enrollees. The data came from Express Scripts – the largest pharmacy benefits manager in the nation – which kept individual information on enrollees confidential to protect their privacy.

“Our partnership with Express Scripts enabled an early look at the prescription use of around one in every seven marketplace enrollees, which is a unique vantage point to examine the ACA. Our findings on specialty medication use in marketplace plans are particularly important, given the general concerns about the rising costs of these medications for consumers,” said senior author Walid F. Gellad, M.D., M.P.H., adjunct scientist at RAND and associate professor at Pitt and the Pittsburgh VA Medical Center.

The team compared people who enrolled in marketplace plans “early” (October 2013 through February 2014) and “late” (March through May 2014). They also compared all ACA marketplace enrollees to a matched group of Express Scripts enrollees with employer-based health insurance.

Among the findings:

• People who enrolled in marketplace plans early were four years older on average than those who enrolled near the enrollment deadline and filled twice as many prescriptions in the first month of enrollment.

• Marketplace enrollees lived in areas where median family income was 9 percent lower than those in employer-sponsored plans.

• ACA marketplace enrollees, as a whole, filled fewer prescriptions and spent less on average per person than those with employer-based coverage, suggesting that the marketplaces effectively pooled risk – attracting both healthy and sick enrollees – in their first year.

• Early marketplace enrollees had comparable medication use to people in employer-sponsored plans but had higher out-of-pocket costs, particularly for specialty drugs.

• Marketplace enrollees had higher use of hepatitis C medications and markedly higher use of HIV medications than those with employer-based coverage.

“From a public health perspective, our analysis indicates that the ACA is successfully helping more vulnerable populations with lower incomes gain access to medications needed to treat chronic and acute conditions,” said Dr. Donohue. “Given the unprecedented expansion of insurance coverage with the ACA, close monitoring of its impact must continue.”

The analysis also shows that the ACA marketplaces staved off early concerns about skyrocketing insurance premiums by successfully attracting younger, healthier enrollees to offset higher costs from older, less healthy people, Dr. Donohue added.

Additional authors are Eros Papademetriou, M.A., of the Eliassen Group; Sharon G. Frazee, Ph.D., M.P.H., of the Pharmacy Benefits Management Institute; Rochelle R. Henderson, Ph.D., of Express Scripts; Christine Eibner, Ph.D., and Andrew Mulcahy, Ph.D., both of RAND; Ateev Mehrotra, M.D., M.P.H., of RAND and the Harvard Medical School; Can Cui, M.A., of the University of Texas at Austin; Bradley D. Stein, M.D., Ph.D., of RAND and Pitt; and Shivum Bharill, of the University of Michigan.

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